Study on the dynamical spin-crossover phenomenon coupled with spinm and charge, and its multifunctionalities

自旋与电荷耦合的动态自旋交叉现象及其多功能性研究

• 批准号: 15350078
• 负责人: KOJIMA Norimichi
• 金额: $ 9.34万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15350078/
• 关键词: charge transfer phase transition; spin-crossover; ferromagnetism; mixed-valence complex; photo-isomerization; photo-control; organic-inorganic hybrid complex; charge transfer interaction; 有機。無機複合錯体; 配位子場; スピンエントロピー; 非対称配位子

In this project, we have synthesized dithiooxalato-bridged iron mixed-valence complexes, (n-C_nH_<2n+1>)_4N[Fe^<II>Fe^<III>(dto)_3] (n=3-6, dto=C_2O_2S_2) and investigated a spin-entropy driven charge transfer phase transition around 120 K, where the electrons of Avogadro's constant transfer cooperatively between the Fe^<II> and Fe^<III> sites, and a ferromagnetic transition at 6.5 K for (n-C_3H_7)_4N[Fe^<II>Fe^<III>(dto)_3]. The charge transfer phase transition takes place for n=3 and 4, while it does not take place between 300 K and 4 K for n=5 and 6. The charge transfer phase transition and the ferromagnetic transition remarkably depend on the hexagonal ring size in the two-dimensional honeycomb network structure of [Fe^<II>Fe^<III>(dto)_3]_∞. The increase of cation size expands the honeycomb ring, which stabilizes the higher temperature phase with Fe^<II> (S=2) and Fe^<III> (S=1/2). Contrary, the contraction of the honeycomb ring stabilizes the lower temperature phase with Fe^<II> (S=0) and Fe^<III> (S=5/2), which was supported by the external pressure effect on the charge transfer phase transition.In order to control the magnetic properties and the electronic state in the dto-bridged iron mixed-valence system by means of photo-irradiation, we have synthesized a photo-sensitive organic-inorganic hybrid system, (SP)[Fe^<II>Fe^<III>(dto)_3] (SP=spiropyran), and investigated the photo-induced effect on the magnetic properties. The UV irradiation changes the structure of spiropyran from the closed form to the open one in (SP)[Fe^<II>Fe^<III>(dto)_3]. The photochromism in spiropyran induces the charge transfer phase transition in the two-dimensional honeycomb network structure of [Fe^<II>Fe^<III>(dto)_3]_∞, and changes the ferromagnetic transition temperature.

本项目合成了二硫代草酸根桥联的铁混合价配合物（n-C_nH_&lt;2n+1&gt;）_4N[Fe^<II>Fe^<III>（dto）_3]（n=3-6，dto=C_2O_2S_2），并研究了120 K左右自旋熵驱动的电荷转移相变，其中阿伏加德罗常数电子在Fe^<II>和Fe^<III>位之间协同转移，以及（n-C_3 H_7）_4N[Fe^ Fe^（dto）_3]在6.5 K下的铁磁转变<II><III>。当n =5和6时，在300 ~ 4K之间不发生电荷转移相变。[Fe^ Fe^（dto）_3]_∞的电荷转移相变和铁磁相变显著依赖于二维蜂窝网络结构中六方环的尺寸<II><III>。阳离子尺寸的增加使蜂窝环扩大，这使具有Fe^<II>（S=2）和Fe^<III>（S=1/2）的高温相稳定。为了<II><III>利用光辐射调控dto桥联铁混合价体系的磁性和电子态，我们合成了一种光敏有机-无机杂化体系（SP）[Fe^<II>Fe^<III>（dto）_3]（SP=螺吡喃），并研究了光诱导对磁性的影响。紫外光照射使（SP）[Fe^ Fe^（dto）_3]中螺吡喃的结构由封闭型转变为开放型<II><III>。螺吡喃的光致变色作用引起了[Fe^ Fe^（dto）3] ∞二维蜂窝状网络结构的电荷转移相变<II><III>，改变了铁磁转变温度。

项目成果

小島憲道, 守友浩: "集積型金属錯体の科学-物質機能の多様性を求めて"大川尚士,伊藤翼 編,化学同人. 273(113-117) (2003)

小岛纪道、森友浩：“综合金属配合物的科学 - 寻找材料功能的多样性” Naoshi Okawa、Tsubasa Ito (eds.)，Kagaku Doujin 273(113-117) (2003)。

Crystal Structure and Structural Transition Caused by Charge-transfer Phase Transition for Iron Mixed-valence Complex, (n-C_3H_7)_4N[Fe^<II>Fe^<III>(dto)_3](dto = C_2O_2S_2)

铁混价配合物(n-C_3H_7)_4N[Fe^<II>Fe^<III>(dto)_3](dto = C_2O_2S_2)的晶体结构和电荷转移相变引起的结构转变

• 发表时间: 2004
• 期刊: Solid State Commun. 130
• 作者: M.Itoi;A.Taira;M.Enomoto;N.Matsushita;N.Kojima;Y.Kobayashi;K.Asai;K.Koyama;T.Nakano;Y.Uwatoko;J.Yamaura
• 通讯作者: J.Yamaura

N.Kojima, M.Itoi, Y.Ono, M.Okubo, M.Enomoto: "Spin-entropy driven charge-transfer phase transition in iron mixed-Valence system."Materials Science. 21. 181-189 (2003)

N.Kojima、M.Itoi、Y.Ono、M.Okubo、M.Enomoto：“铁混合价体系中自旋熵驱动的电荷转移相变。”材料科学。

Control of Charge Transfer Phase Transition in Iron Mixed-valence System, (n-C_nH_<n+1>)_4N[Fe^<II>Fe^<III>(dto)_3](n=3-6 ; dto=C_2O_2S_2).

铁混价体系中电荷转移相变的控制，(n-C_nH_<n 1>)_4N[Fe^<II>Fe^<III>(dto)_3](n=3-6 ; dto=C_2O_2S_2)

• 发表时间: 2004
• 期刊: Hyperfine Interactions 156-157
• 作者: N.Kojima;Y.Ono;Y.Kobayashi;M.Seto
• 通讯作者: M.Seto

Control of Charge Transfer Phase Transition in Iron Mixed-valence System, (n-C_nH_<2n+1>)_4N[Fe^<II>Fe^<III>(dto)_3)(n = 3-6 ; dto = C_2O_2S_2).

铁混价体系中电荷转移相变的控制，(n-C_nH_<2n 1>)_4N[Fe^<II>Fe^<III>(dto)_3)(n = 3-6 ; dto = C_2O_2S_2)

• 发表时间: 2004
• 期刊: Hyperfine Interactions 156-157
• 作者: N.Kojima;Y.Ono;Y.Kobayashi;M.Seto
• 通讯作者: M.Seto